On August 2, 1964, the U.S. destroyer USS Maddox reported being attacked by North Vietnamese patrol boats in the Gulf of Tonkin. A second reported attack two nights later became the subject of later controversy and debate. The incidents led President Lyndon B. Johnson to request broad authority from Congress to respond. Congress soon passed the Gulf of Tonkin Resolution, which effectively gave the president wide latitude to escalate U.S. involvement in Vietnam. The episode became a key turning point in deepening the Vietnam War. Later investigations raised questions about what exactly happened in the gulf.